progress

trace.js

+function run_trm(t) {
+  switch (t.tag) {
+  case "trm_var":
+    var v = lookup_var(t.name);
+    return res_val(v);
+  case "trm_cst":
+    return res_val({ tag: "val_cst", cst: t.cst });
+  case "trm_let":
+    return if_success(run_trm(t.t1), function(v1) {
+      env_push(t.name, v1);
+      var res = run_trm(t.t2);
+      env_pop();
+      return res;
+    });
+  case "trm_seq":
+    return if_success(run_trm(t.t1), function(v1) {
+      return if_success(run_trm(t.t2), function (v2) {
+        return(res_val(v2));        
+      });
+    });
+  case "trm_alloc":
+    var loc = heap_alloc();
+    return res_val({ tag: "val_loc", loc: loc });
+  case "trm_get":
+    return if_success(run_trm(t.loc), function(loc) {
+      var v = heap_get(loc, t.field);
+      return res_val(v);
+    });
+  case "trm_set":
+    return if_success(run_trm(t.loc), function(loc) {
+      return if_success(run_trm(t.arg), function(arg) {
+        heap_set(loc, t.field, arg);
+        return res_val(arg);
+      });
+    });
+  case "trm_if":
+    return if_success(run_trm(t.cond), function(cond) {
+      return if_bool(cond, function(b) {
+        if (b) {
+          return if_success(run_trm(t.then), function(v) {
+            return res_val(v);
+          });
+        } else if (t.else_option !== undefined) {
+          return if_success(run_trm(t.else), function(v) {
+            return res_val(v);
+          });
+        } else {
+          return res_val({tag:"val_cst", cst:{tag:"cst_bool", bool:true}});
+        }
+      });
+    });
+  }
+}
\ No newline at end of file